It is well-known in the arts relating hereto to employ a flow-pressure compensated or "load-plus" valve to maintain the discharge pressure of a variable displacement pump above a minimum pressure level and also above a load pressure generated in a fluid actuator, during a working range of the pump. This type of valve is fully disclosed in U.S. Pat. No. 4,116,587, issued on Sept. 26, 1978 to Kenneth P. Liesener, and assigned to the assignee of this application. The valve functions to sense a load pressure signal and to automatically communicate and modulate an actuator pressure signal for controlling the position of a swash plate of the pump to maintain the pump at its desired displacement.
Should the rating or working horsepower consumption range of the pump be exceeded, it is further desirable to modify the actuator pressure signal to destroke the pump to prevent potential damage thereto and to related components of the fluid circuit. U.S. Pat. No. 3,999,892, issued on Dec. 28, 1976 to Allyn J. Hein, and also assigned to the assignee of this application, discloses a pump control system wherein the actuator pressure signal is vented to tank when such horsepower consumption range is exceeded. This periodic bleeding-off of the actuator pressure signal results in an undesirable loss of system horsepower. Furthermore, the integrated fluid circuit does not adapt the horsepower limiting feature to be incorporated into a module adapted for use with pumps of various sizes.
The present invention is directed to overcoming one or more of the problems as set forth above.